The purpose of the proposed project is to evaluate the effects of nutritional supplementation on biologic and behavioral health outcomes inundernourished persons with chronic airflow limitation (CAL). The hypothesis to be tested is: Undernourished subjects with activity-induced dyspnea and an improvement in nutritional status, exercise tolerance, and quality of life when compared to subjects who receive their usual dietr. Thirty-two undernourished subjects with stable chronic airflow limitation will be randomized into two groups: (a) control group (maintain usual diet) and (b) supplementation group. Data will be collected in a General Clinical Research Center as baseline (enrollment), 6 and 12 weeks. Changes over time in nutritional status, exercise tolerance, activity-induced dyspnea, and quality of life will be measured. The inclusion of both biological and behavioral variables allows for fully evaluating the subjects' response to dietary supplementation.